Up to date information on both Windows and Macintosh compatibility and system requirements for EndNote are listed here.
Please ensure your home and work EndNote version are the same if you plan on working with EndNote libraries between your office PC and your home computer.
Use of EndNote with cloud storage services
Clarivate advises that the EndNote software is not compatible with Dropbox or other cloud storage services. These services can be used to store a backup compressed copy of an EndNote Library but Clarivate advises against opening and/or using a Library from a cloud-storage location such as Dropbox, OneDrive, Google Drive, SharePoint, iCloud, etc.
If you save your EndNote Library to a cloud storage service it is recommended that you copy the files to another location on your computer before you open them. Using Your EndNote Library from a cloud storage service may corrupt your EndNote Library over time.
EndNote, Reference Manager, & ProCite: Compatibility with Dropbox and other Cloud storage
For further details contact Clarivate Technical Support.
Note for Macintosh users:
Apple's macOS versions 10.12 (Sierra), 10.13 (High Sierra), 10.14 (Mojave), 10.15 (Catalina) and 11.0 (Big Sur) contain features to save the contents of the Documents folder to the iCloud and to "optimize" storage by storing less-used files only in iCloud online.
Information on how to disable this setting is available from Add your Desktop and Documents files to iCloud Drive.
Other useful guides for Mac users